One of the biggest (and also one of the most under-the-radar) surprises of last season was the sudden emergence of Ryon Healy in the second half of the year. Healy, a Minor Leaguer on the fringe of even being considered a “prospect”, was called up on July 15 and proceeded to put up monster numbers in 72 games. Entering 2017 with a starting gig in hand, both the Athletics and Healy hope last year’s production didn’t just happen by accident.

Drafted in the third round of the ‘13 MLB Draft, Healy struggled mightily in his first pro season. He managed a putrid .230/.255/.402 line in 47 games between Rookie ball and Class A. Healy had a decent season for Class A Advanced Stockton the following year, yet still wasn’t really given a second glance by most around baseball. Entering ‘15, he was ranked as the 20th best prospect in the organization by MLB.com.

After putting up a so-so season with just 10 homers in 124 games for Double-A Midland that year, Healy dropped off the radar almost entirely. He played only three games for the A’s in Spring Training and started the year at Double-A with low expectations. It was then that something clicked, and Healy began the year mashing at Double-A, with eight homers in just 36 games before getting a call up to Triple-A. He continued to hit there and before long, found himself on the A’s, where he never slowed down.

Healy has talked about making a swing change before last season, but could it have been that simple of a fix (basically lowering his hands) that made Healy go from fringe prospect to big league slugger? Taking a closer look at Healy’s numbers from last year, there’s no denying the consistent power his swing produced. His 134 wRC+ was fourth among hitters with at least 250 plate appearances at his position, behind three of the best offensive third basemen in baseball — Josh Donaldson, Kris Bryant and Matt Carpenter. His .219 ISO (isolated power) was about middle of the pack. At his best he doesn’t really project as a legitimate threat to hit above 30 homers in a full year in the bigs, though his ceiling isn’t far off.

Not only can Healy hit 20-25 homers this year, he can do so with a more-than reasonable batting average. He was a career .293 hitter in the Minors, so the .305 average he put up for the A’s wasn’t too out of the ordinary. Where Healy could stand to improve is his walk rate. His 4.2 BB% last year is well below average, especially at his position. He doesn’t swing and miss a ton, but his pitch selection needs work.

While Healy’s 32.7 O-Swing% (swing percentage on pitches outside of the zone) is slightly higher than average, his 56.8 Z-Swing% (percentage of pitches swung at inside of the zone) is alarmingly below average. With the same qualifier (250 plate appearances), Healy had the 12th lowest Z-Swing% in all of baseball. It’s certainly possible to have success with a number like this, as evidenced by players like Martin Prado (53.5) and Mookie Betts (58.4). If he’s going to continue to let so many strikes go by, however, he’ll need to cut down on his swings outside of the zone. Only one hitter in baseball had a lower Z-Swing and higher O-Swing last year, and that was Jose Iglesias in what was arguably a career-worst season for him.

The odds of Healy putting up numbers resembling his ‘16 second half throughout a full season are very slim. That doesn’t mean Healy will be a total bust this year, though. ZiPS projections have him with 21 homers, 75 RBIs and a .267/.305.445 line. His projected 1.6 WAR is just 29th highest among third basemen, which is likely hindered a bit by his below-average defense.

Athletics fans shouldn’t expect Healy to fall off the face of the Earth this season, and they also shouldn’t expect him to vastly improve on his ‘16 performance. Look for Healy to simply put up above-average offense, and he should hold up well in the middle of Oakland’s lineup.

Rich Arleo is a freelance sports writer and editor who covers Major League Baseball and fantasy sports. You can follow him on Twitter, @Rarleo.